Multipartite Entanglement at Finite Temperature
Authors: Gabbrielli M., Smerzi A., Pezzè L.
Autors Affiliation: INO CNR, QSTAR, Largo Enrico Fermi 2, I-50125 Florence, Italy
Abstract: The interplay of quantum and thermal fluctuations in the vicinity of a quantum critical point characterizes the physics of strongly correlated systems. Here we investigate this interplay from a quantum information perspective presenting the universal phase diagram of the quantum Fisher information at a quantum phase transition. Different regions in the diagram are identified by characteristic scaling laws of the quantum Fisher information with respect to temperature. This feature has immediate consequences on the thermal robustness of quantum coherence and multipartite entanglement. We support the theoretical predictions with the analysis of paradigmatic spin systems showing symmetry-breaking quantum phase transitions and free-fermion models characterized by topological phases. In particular we show that topological systems are characterized by the survival of large multipartite entanglement, reaching the Heisenberg limit at finite temperature.
Journal/Review: SCIENTIFIC REPORTS
Volume: 8 Pages from: 15663-1 to: 15663-18
KeyWords: Bose-Einstein condensate; infinitely coordinated systems; many-body system; quantum criticality; fisher informationDOI: 10.1038/s41598-018-31761-3Citations: 8data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2019-10-13References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here